Study reveals dramatic rise in chronic kidney disease
Dr. Marc Siegel, a senior medical analyst, appeared on ‘America’s Newsroom’ to discuss the increasing incidence of chronic kidney disease worldwide, preventative measures, and the potential benefits of weight-loss medications for those affected.
A puzzling kind of kidney disease that has heavily impacted young to middle-aged agricultural workers in Central America and South Asia seems to be emerging in Texas. This condition, referred to as chronic kidney disease of unknown etiology (CKDu) or Mesoamerican nephropathy, has researchers scratching their heads since it affects healthy adults who do not exhibit common risk factors for kidney failure.
Chronic kidney disease varies in severity and may lead to serious complications such as fluid buildup, high blood pressure, heart disease, strokes, and even premature death, as highlighted by the Centers for Disease Control and Prevention.
In contrast to conventional kidney disease cases, CKDu occurs in the absence of typical risk factors like diabetes, high blood pressure, and glomerulonephritis, a condition that causes inflammation in the kidneys’ filtering units. Dr. Gokul Paidi, a family medicine physician at Community Healthcare Network in New York, emphasizes that CKDu mainly strikes young to middle-aged adults—especially men—in agricultural and manual labor jobs located in hot, resource-limited areas.
Over the years, several regional kidney diseases have been characterized, but not all align with CKDu. Paidi points out that Balkan endemic nephropathy has been known since the 1950s, Itai itai disease in Japan was linked to rice contaminated with cadmium, and Sri Lankan nephropathy has been studied since the 1990s. Mesoamerican nephropathy, first noted among sugarcane workers in El Salvador and Nicaragua in the late 1990s, is now being documented in the U.S.
Other countries have experienced similar local outbreaks, including Sri Lanka, India, rural Thailand, and specific regions in Mexico. Paidi suggests that these instances are likely interconnected, emerging clusters of an underlying disease process manifesting in various farming and industrial settings around the globe.
In Houston, physicians at safety-net hospitals like Ben Taub have encountered otherwise healthy young men in their 20s and 30s who presented with kidney failure, some exhibiting “Coca-Cola-colored urine.” These patients often lack the usual risk factors for kidney disease, creating a concerning picture.
The troubling thing, Paidi observes, is how closely these Texas cases resemble those initially seen in Central America. The majority of affected individuals are undocumented workers from Mexico and Central America engaged in construction or outdoor jobs under extreme heat. They often lack sufficient access to water breaks, which is critical in hot working conditions.
According to a review of Harris County hospital data, nearly one in six emergency dialysis cases in uninsured or undocumented individuals presented no clear cause, aligning with the CKDu pattern. Some patients hesitate to seek medical attention or partake in research due to their immigration status, complicating efforts to monitor the disease’s progression and catch kidney damage before it becomes severe.
Common symptoms of CKDu
CKDu is often referred to as a “silent disease,” primarily because many patients show no early symptoms. Most individuals, especially those working in sugarcane fields, only realize they have kidney issues after routine blood tests reveal the problem, says Dr. Richard J. Johnson, an expert on kidney diseases.
As the disease progresses, it can produce symptoms characteristic of severe chronic kidney disease, which include fatigue, sleep disturbances, nausea, weakness, and shortness of breath due to anemia. By the time patients exhibit symptoms, they often are already approaching end-stage kidney disease.
People suffering from CKDu tend to reside in areas lacking resources, where dialysis and transplants are generally unaffordable or difficult to access, increasing the risk of early mortality, Paidi explains.
Potential causes
Experts suspect that heat stress is a significant factor contributing to CKDu, although the precise cause remains elusive. They believe a blend of occupational and environmental elements may gradually harm the kidneys. Outdoor labor can lead to heat stress and dehydration, with potential exacerbation from exposure to pesticides and smoke from burning sugarcane.
Additionally, workers often face challenges like potentially unsafe drinking water and depend on over-the-counter pain relievers, which, when combined with dehydration and heat exposure, may further put strain on their kidneys. Some professionals advocate for improved hydration and shade at work, along with shorter working hours and earlier starts to reduce kidney damage.
Diagnosis and treatment
There is no specific test to diagnose CKDu. Instead, physicians identify it by excluding other causes of chronic kidney disease and assessing patients’ occupational and environmental exposures. Kidney biopsies, which are the most definitive method, are not practical for widespread use.
Currently, there isn’t a targeted treatment for CKDu. Management primarily revolves around regulating blood pressure and preventing further kidney damage, including avoiding NSAIDs. In advanced stages, treatment may involve dialysis or transplantation. Although some patients use ACE inhibitors to manage their blood pressure, these medications can sometimes worsen kidney function for those already dehydrated, which is a significant concern.
CKDu tends to progress quickly, often over a few years, and both dialysis and transplantation options are seldom available, leading to high mortality rates. Therefore, screening for this condition is crucial.
For individuals working in agricultural or outdoor jobs in hot climates, Paidi suggests regular kidney function checks with their primary care doctor—ideally, at least twice a year. A simple blood test measuring creatinine levels, along with a urine test for protein, can identify early changes long before symptoms arise.
